Various industries have networks associated with them. One such industry is the utility industry that manages a power grid. The power grid may include one or all of the following: electricity generation, electric power transmission, and electricity distribution. Electricity may be generated using generating stations, such as a coal fire power plant, a nuclear power plant, etc. For efficiency purposes, the generated electrical power is stepped up to a very high voltage (such as, for example, 345K Volts) and transmitted over transmission lines. The transmission lines may transmit the power long distances, such as across state lines or across international boundaries, until it reaches its wholesale customer, which may be a company that owns the local distribution network. The transmission lines may terminate at a transmission substation, which may step down the very high voltage to an intermediate voltage (such as, for ex ample, 138K Volts). From a transmission substation, smaller transmission lines (such as, for example, sub-transmission lines) transmit the intermediate voltage to distribution substations. At the distribution substations, the intermediate voltage may be again stepped down to a “medium voltage” (such as, for example, from 4K Volts to 23K Volts). One or more feeder circuits may emanate from the distribution substations. For example, four to tens of feeder circuits may emanate from the distribution substation. The feeder circuit is a 3-phase circuit comprising 4 wires (three wires for each of the 3 phases and one wire for neutral). Feeder circuits may be routed either above ground (on poles) or underground. The voltage on the feeder circuits may be tapped off periodically using distribution transformers, which step down the voltage from “medium voltage” to the consumer voltage (such as, for example, 120V). The consumer voltage may then be used by the consumers.
For consumers, steady and sufficient power supplies are important. Generally, the steady power can be produced with a typical coal, gas, or nuclear plant if only the capacity of the generator is enough and a steady and sufficient supply of fuel is ensured. However, consumers' power demand is not steady and the demand usually is higher during daytime than during nighttime. That is to say, the load of the power grid has a peak which generally occurs at daytime and a valley which often occurs at nighttime, as illustrated in FIG. 1A. Therefore, the load of the power grid is highly volatile.
To tackle these problems, one of emerging approaches is to manage the demand to match the limited supply. A typical solution of load management is peak load shaving (hereinafter referred to load shaving in short), which is to shave the load by reducing the peak demand and increasing the valley demand or moving some of the demand from the peak load periods to the valley load periods. The load shaving can include load clipping and load shifting. As illustrated in FIG. 1B, the load clipping refers to a load management measure which includes clipping the peak load by, for example, turning off some electrical equipment. The peak shifting refers to a load management measure which includes shifting the peak load to other times while keeping the load curve intact by, for example, making some electrical equipment operate at off-peak hours (for instance, advancing or postponing operations of a manufactory several hour to avoid peak hours). The valley filling refers to arranging some loads to the valley hours so as to fill the load valley.
With a high economic growth, the power demand is constantly increasing but the energy consumption is not optimized. This causes rapid increase of energy consumption and even greater increase of peak consumption, which in turn results in a peak load growth greater than the base load growth. That is, there is a greater difference between the peak load and the valley load. The utility has to either depend on the increasingly more expensive power supply which will result in a very low return on investment, or deny service to customers which would badly impact customer experience and decrease customer satisfaction.
Therefore, the growth of peak-valley difference will induce many problems such as a lower asset usage, a higher asset renew rate, a lower return of investment (“ROI”), a higher supply pressure, a lower supply reliability, lower customer satisfaction, revenue loss during blackout, load shedding, etc. Moreover, it may increase the system operation balancing difficulties. Accordingly, there may be a need to better manage the load of a power grid so as to balance load.